Axially arranged rotary threshing or separating systems have long been in use in agricultural combines for threshing crops to separate grain from crop residue, also referred to as material other than grain (MOG). Such axially arranged systems typically include at least one cylindrical rotor rotated within a cage or concave, with the rotor and surrounding concave being oriented so as to extend forwardly to rearwardly within the combine.
During operation of the combine, crop material is fed or directed into a circumferential passage between the rotor and the concave and is carried rearwardly along a generally helical path through such passage by rotation of the rotor as grain is threshed from the crop material. The flow of crop residue remaining between the rotor and concave after threshing is typically discharged or expelled at a rear or downstream end of the rotor. After discharge from the threshing system, the crop residue is typically directed into a crop residue distribution system located below and rearwardly of the rear end of the rotor. The crop residue distribution system typically includes a rotary beater or chopper or other apparatus that conveys and/or chops and propels the residue rearwardly towards an area within the rear end of the combine, hereinafter referred to as a distribution chamber. The crop residue provided within the distribution chamber may either be discharged therefrom onto a field as a windrow or be directed into a chopper and/or spreader mounted on or at the rear end of the combine that is operable for spreading the residue over a swath of a field.
Windrowing typically occurs when, under certain conditions and in certain localities, users desire to retain the crop residue for post-processing. In such cases, the residue, which may be chopped or un-chopped, is discharged from the combine, without entering the chopper/spreader, to form a windrow directly behind the combine. Such windrow may, for example, contain only straw residue or both straw residue and chaff, and may typically be produced by the expulsion of the residue flow over the top of the chopper/spreader, such as when the crop residue is discharged through a rear opening of the distribution chamber. As is generally understood, a windrow door is typically positioned at the rear opening and is pivotable between a closed position, wherein the crop residue is diverted into the chopper/spreader, and an open position, wherein the crop residue is directed over the chopper/spreader and through the rear opening.
When the crop residue is to be discharged onto a field to form a windrow, it is typically preferred that the crop residue be distributed onto a windrow chute extending from the rear opening to allow for the formation of a desirable windrow shape. This generally requires that the rear opening be rather large. Unfortunately, when the windrow door is moved to the open position and, thus, forms a large opening at the rear end of the combine, the crop residue may often fail to contact the window chute (e.g., by flowing directly over the windrow chute and onto the field). This leads to the crop residue being discharged onto the field at a very high velocity, which may result in the formation of an undesirable windrow.
Accordingly, a windrow door assembly that is capable of accurately directing the flow of crop residue onto a windrow chute for subsequent discharge onto a field would be welcomed in the technology.